Early on in the life of my Saito 100 it developed play in the shaft from the same problem. Bearing failure with the presence of rust. No warrenty even after I explained that it was only on its third gallon of 30% nitro with the use of after run oil. Break in was very cautiously by the book and the engine was not abused. Paying for the repair hurt. Several small failures later and the obvious lack of gusto from a season of almost daily use, I decided to move on. Enter the season of power and smiles. My move to the YS 110 was very positive. It is still, what I consider to be, one of my best investments in R/C. Later, Joe

it took a lot of convincing joe but on about the eighth shot at it he finally gave in!(might have somthing to do with me mintioning i was a member of rcu).but i did break in to the book and ran it dry, and then gave it a few more spins, then oiled it, so as i told him there was no way the bearings should have been rusted, and i thanked him when he said ok!!

Wonder if its the extra boreXstroke packed in a 91 case that causes too much side thrust on the bearings. Also wonder if upping the oil content would help this (IE. YS 20/20) ? any comments?

I don't know. I can see if it was neglect of proper daily mainenance. Also the oil content of 30% is pretty high. But that is in the past. For now I will enjoy the power of YS. Its got about 50 flights on it already and I will post the performance/longevity, good or bad. first YS purchase so only time will tell. Joe

hi Lee, i have been on the engines threads and talking to some of the OLD TIMERS and a bunch of them convinced me to use at least 4oz of castor in 1 gal fuel and do what ive been doing and these engines should last a lot longer than my approx 26hrs that i got on my saito 100. theres some pretty knowledgeble guys there that been doing this for up to and beyond 40 years and have some pretty old orignal saitos so im giving them the benifit of the dought and there probley right. i hope so i dont want to have to whine like that again, i was starting to embarass myself.ha ha!!!

Gary

Anybody think the u can do 60 is more 3d capable than an Extreme Flight 68" 54 Yak?

AHHH HMMMMMMM AAAA UUUUUUUHHHH NO

But that still dont stop me from flying mine[8D]

It still flies great and ive had the most fun with it ive had in all my non electrics.

its like ive said before, every plane is just a step to the next plane, an d no the ucd is not the best but it is a step forward!

I don't know, but soon I'll be able to tell you. I just completed my EF Yak 54, and I've been flying my .60 size UCD since late summer/fall. Of course, the weather here will have to cooperate so it may be quite a while.....

This just reminds me of what a let down Christmass was. Tore the add out of a magazine, so there would not be any confusion, gave it to my niece in early November. She sees Santa on a regular basis. Come Chrismass, no big box. I did get an envelope with a gift certificate for $400.00....................................... to a LHS that dosn't carry EXTREME FLIGHT YAKS !!!!!!!!!!!!!!!!!! Women. They thought I could just run out and buy it. Well, its the thought that counts. Now I have a gift certificate to a LHS that may as well be Tower Hobbies annex, as all they carry is generic stuff. I'll figure something out. Won't give up on the UCD yet, even after two years I still enjoy it. Later, Joe

Hi people, I just picked up a used UCD 46/YS 63 the price was to good
to pass up, The plane is in great shape and the YS sounds and runs good
though it has some time on it.. Anyway anyone know the best prop setup
for this combo?? Was trying to find an APC 13x4W but I did not see one
listed at Towers?? Thanks for any info...

gjeffers & cumn thru,

Just a note about my Saito 100. I too have a bearing noise in mine, very rough when I spin the prop. I have maybe 12 flights on it. I broke it in as per the instructions. We have had quite a bit more rain for the past couple of years than is usual. So... when the bearings started to make noise I attributed it to the humidity. I just disassembled the engine tonight and found rusted bearings alright... along with everything else in the engine. Cam, crank, rockers. And afterrun oil running out from everywhere. The compression on this engine is awesome. Funny thing though, I also use afterrun oil EVERY time I put the airplane up after the days flying. I never miss this, not on any of my engines. This Saito 100 is the only one I have ever had rust up. Now for the most interesting thing... I also have a Saito 72 that is a year older w/ about 40 flights. broke it in the same as the 100, same afterrun oil and kept in the garage same as the 100 but this engine has perfect bearings, very smooth.

I think there may be a problem w/ the Saito 100's, JMO though. Maybe packaged during very humid weather. I don't know.

This engine is still under warranty but I am not sending it in. I am installing ceramic bearings from Boca Bearing. Maybe I can get a few hundred more RPM's?

Tom...

hmm interesting stuff.. can you tell if the bearings differ in metal compositon from the 82,or say maybee a cheaper bearing? very odd that this only happens on the 100s.. I have personally never have owned one but wonder what it is causing that..

hey tknobby, got my saito back and ill see how long these bearings last because im gonna do a chart on all things and hours done to and run in on it and if it dont last its going back and them and you guys will here, good or bad so if they turn out all right ill post here and if they dive same goes.

there is one thing im gonna do different since these engines are inverted while stored im gonna try turning the plane upside down every few days when i walk by while stored since all the oil seames to run to the valve covers and get the oil back to the bottom and turn the prop a few times and re-oil the bearings.

later Gary

Tom, with howling bearings and the presence of rust, I would check for lateral play in the shaft. If it moves side to side then you should go ahead and check the cam lobe and push rod ends as well. My cam had a groove wore into it and the pushrod ends were peened over. This was within the first few gallons of fuel with proper break in, supposedly good fuel and regular shutdown maintenance. So give it a good once over so your not tearing it down again after the new ceramic bearings are installed. One good thing about Saito service is that there is a flat $25.00 labor charge. If you need just a carb swapped out or a complete engine overhaul, same $25.00 fee + parts. On another note, if you need something less critical as bearings, for instance, engine block, manifolds, valve covers, etc they offer used parts for 20% off. It all adds up.
Gary, I've read that a good storage method is to hang the plane by its tail so the oil stays on the front bearing and seal. I don't know how that helps the rear main bearing, but who knows? Later, Joe

Joe,
Guess I now know where you have been spending your days!! Guess you can count be as being onboard now too. Brian....

When I wore out the saito 100 on my Ucando it had about 40 gallons through it. I didn’t even notice how bad the front bearings had gotten until someone else brought it to my attention.
The saito was running flawlessly up until the time I decided I better not push my luck and have it looked at.
I brought it to a hobby shop that rebuilds engines. A few days later he called me and said, “This engine must not have been running for you�
I told him it has been my most reliable and best running engine. He said it looked it had sat on the bottom of the ocean for a year.
The front and back bearings were badly rusted, the cam had grooves worn in it and the cylinder wall was scratched. He absolutely couldn’t believe this engine was running at all, never mind running good.
Seeing others have had the same problems it makes you wonder is it me that’s doing something wrong, or is there something else going on?

you guys that are having these problems with rusting bearings should bring attention to horizon because they should know. i did and fought with them and won, but from the sound of things i shouldnt have had to fight them. let them know! call them and ask for dave and tell him, hes the one i convinced there was a problem and i think he need to here from you guys

thanks Gary

Joe, I think gjeffers may have a good idea with repositioning the plane to get the oil back down to the bearings. As far as the front bearing is concerned, it is sealed on both sides w/ nice seals. Afterrun oil will probably not penetrate the seals here. The real problem seems to be the rear bearing. Mine has extreme rust, especially in the area between the bearing and case area(front of bearing). Today I went to a local auto machine shop to have a buddy of mine glass bead the crank. It looked like hell. Kinda like I pulled it out of the ocean.

And yes cumn thru, I will give a very close look at the rest of the engine.

I have been thinking. Maybe the crankcase breather nipple is allowing too much humidity into the engine? I did have a 8 inch piece of tubing on mine which I think should help keep any moisture from entering. Any thoughts?

BTW, I will be installing this onto my new U Can Do 3D. Hopefully folks won't think we've hijacked the thread.

hey tknobby you might be right also about the crankcase vent tubing length having to do with humidity being able to enter the crankcase. if the volume of air being exchanged back and forth from the crankcase is less than the volume of the hose then the outside air will not enter the case.this is with the engine running of course and plugging the line might help when sitting idle. if this makes no sense i might be able to reword it.

Gary

I think that one of the biggest avenues of moisture being introduced into the engine is from the fuel. Ever notice the condensation that forms in a partially filled jug? That is one reason I never let my jug sit in the sun at the field. My truck has a cap and thats where it stays, in the shade. Buying by the case, I keep the remaining stock in a cool dark area. One other way to avoid condensation is to transfer from another jug to keep the one that you bring to the field full, whenever possible. I've often thought of one of those collapsible jugs that won't allow air in as fuel is pumped out. Like a bladder. As others have reported, I have other engines using the same fuel and under the same conditions that never rusted out. Joe

Gary,

Thats kinda what I've been thinking too. Maybe inject some afterrun oil into the breather, flip the prop over a dozen times and clamp off the breather hose. Might be best to clamp when the piston is at bottom dead center. At that time the crankcase volume would be the least.

I don't think applying afterrun oil into the carb throat will get a good quantity into the crankcase. The oil would have to run past the piston and ring then into the crankcase. Unlike a 2 stroke where the oil enters the crankcase first.

Seems the worst rust on my 100 was in the rear bearing and counterweigth on the crank... closest to the breather hole.

Tom...

your right joe about the air entering the can while fueling, but as far as myself i have been a gasoline tanker driver for over 15 of my 27years of being a truck driver and im well schooled on vapor recovery and thats why i plug into my vapor line from my tank and run it into my can ( that i also keep in the shade) and this procedure keeps outside air from entering the fuel can to a minimum. believe me if this engine rusts there is a problem.


your right too Tom, I will heed your advice and plug with piston in the down position.

Gary

Hi, I just broke in my new O.S. .91 FX for the U Can Do. My question is, will this engine hover this plane with an APC 15x4W propeller? Or will this engine hover it at all? Thanks.

I have the OS .91 in my UCD and it will certainly hover. Mine hovers at about 1/2 to 2/3 throttle with an APC 15X6 prop. My UCD is a little heavy (8.2 lbs) largely because of all the tail weight I had to add. I would like it to rocket out of a hover, but it won't quite do that. Still, vertical (for IMAC type maneuvers) is almost limitless. I was actually going to try an APC 16X4 if I can get my hands on one.